Antibiotic susceptibilities of enterococci isolated from Turkish children

To evaluate the antibiotic resistance rates of enterococci isolated at Hacettepe Children's Hospital, in vitro antibiotic susceptibility tests were performed in 77 enterococci (32 hospital, 45 nonhospital strains) isolated from various clinical specimens in 1994. Microbroth dilution tests against ampicillin, vancomycin, gentamicin and streptomycin were performed according to the NCCLS standards. High-level resistance to aminoglycosides was investigated. Ampicillin resistance rates were 21.9 percent and 2.2 percent for hospital and nonhospital strains, respectively (p < 0.01). The same rates were 46.9 and 13.3 percent for gentamicin (p < 0.01), and 15.6 and 13.3 percent for streptomycin (p = 0.25). No resistance was detected against vancomycin. Six strains (7.8%) showed high-level resistance to both aminoglycosides studied. Special attention should be paid to enterococci isolated from hospitalized patients. Appropriate antibiotic use in serious infections can only be achieved by choosing an appropriate regimen according to antibiotic susceptibility tests. Periodic evaluation of the antibiotic susceptibility patterns of enterococci is necessary for the empirical treatment of infections due to these microorganisms.     

A prospective randomized study of Chop versus Chop plus alpha-2B interferon in patients with intermediate and high grade non-Hodgkin's lymphoma: the International Oncology Study Group NHL1 Study .

The addition of a brief alpha interferon regimen to each CHOP induction cycle, plus one year of alpha interferon thrice weekly maintenance therapy, has no early effect on response rates or survival in patients with Intermediate or High grade cell NHL. BACKGROUND: The CHOP (Cyclophosphamide, Adriamycin. Vincristine, Prednisone) regimen is the most widely used first-line therapy for patients with Intermediate or High Grade (IG/HG) non-Hodgkin's lymphoma (NHL). Alpha 2b interferon (INF) enhances response rates and improves survival in low-grade NHL. The International Oncology Study Group (IOSG) conducted a prospective randomized study comparing CHOP alone or combined with INF in patients with IG/HG-NHL. The primary study aim was to compare the objective response rates in these patient cohorts. PATIENTS AND METHODS: Patients with a confirmed diagnosis of measurable NHL of International Working Formulation (IWF) groups D to H histology were randomized to receive CHOP alone or CHOP with 5Mu INF s.c. for 5 days on days 22 to 26 of each 28 day cycle with INF 5 million units (Mu) given three times per week subcutaneously for 52 weeks in those patients who responded to CHOP plus INF. RESULTS: The overall response rates were equivalent in both groups: CHOP alone (214 patients) 81% (complete 55%, partial 26%); CHOP plus INF (221 patients) 80% (complete 54%, partial 26%). At 36 months, the actuarial survival rate was equivalent in both groups. CONCLUSIONS: There is no apparent early advantage in terms of response or survival conferred by adding the study INF regimen to CHOP therapy for patients with IG/HG-NHL.     

Hematopoietic stem cell transplantation from non-replicative hepatitis B virus carriers is safe.

BACKGROUND/AIMS: Hepatitis B virus can cause serious problems in individuals undergoing organ transplantation. The aim of this study was to evaluate the hepatic events among HBs-Ag positive recipients and HBs-Ag negative recipients who received products from hepatitis B virus carriers. METHODS: A total of 151 patients received an allogeneic hematopoietic stem cell transplantation at the Department of Hematology-Oncology, University of Ankara, between June 1989 and June 1998. Among these, eight HBs-Ag positive and four HBs-Ag negative recipients received a product from a hepatitis B virus positive donor. The median follow-up period for these 12 patients was 13.2 months. RESULTS: Three of the eight HBs-Ag positive recipients died (one from hepatic failure); of the remainder, two are HBs-Ag negative, two HBs-Ag positive with normal liver injury tests and one HBs-Ag positive with elevated ALT levels. Of the four HBs-Ag negative recipients who received stem cells from a hepatitis B positive donor, two died; none of the patients in this group became HBs-Ag positive after transplantation. CONCLUSION: Hepatitis B virus infection is a common problem in patients being considered for allogeneic hematopoetic stem cell transplantation, especially in areas where hepatitis B virus infection is endemic. We believe that the presence of HBs-Ag positivity is not an absolute contraindication for allogeneic hematopoetic stem cell transplantation unless the hepatitis B virus is in a replication phase.     

Reaction control of metal-assisted chemical etching for silicon-based zone plate nanostructures

Metal-assisted chemical etching (MACE) reaction parameters were investigated for the fabrication of specially designed silicon-based X-ray zone plate nanostructures using a gold catalyst pattern and etching solutions composed of HF and H₂O₂. Etching depth, zone verticality and zone roughness were studied as a function of etching solution composition, temperature and processing time. Homogeneous, vertical etching with increasing depth is observed at increasing H₂O₂ concentrations and elevated processing temperatures, implying a balance in the hole injection and silica dissolution kinetics at the gold–silicon interface. The etching depth decreases and zone roughness increases at the highest investigated H₂O₂ concentration and temperature. Possible reasons for these observations are discussed based on reaction chemistry and zone plate design. Optimum MACE conditions are found at HF : H₂O₂ concentrations of 4.7 M : 0.68 M and room temperature with an etching rate of ≈0.7 μm min⁻¹, which is about an order of magnitude higher than previous reports. Moreover, our results show that a grid catalyst design is important for successful fabrication of vertical high aspect ratio silicon nanostructures.

Specially designed X-ray zone plates with high aspect-ratios have been fabricated via metal-assisted chemical etching, by controlling the reaction kinetics.     

The inappropriate use of HbA1c testing to monitor glycemia: is there evidence in laboratory data?

RATIONALE, AIMS AND OBJECTIVES: Diabetes is a chronic illness and have relatively high prevalence. Glycemic control is fundamental to the management of diabetes. Hemoglobin A1c (HbA1c) is a commonly used laboratory test to monitor glycemia and to manage diabetes. This study aimed to assess the appropriateness of the frequency of HbA1c test order with respect to the commonly approved guidelines for monitoring glycaemia of patients. METHODS: To assess the rate of inappropriate test orders, laboratory records of HbA1c tests ordered between 2002 and 2004 were evaluated. Inappropriate orders were defined as any order for a given patient that takes place within a 29- or 89-day-period following the previous HbA1c order. The effects of various parameters, like ordering clinics, the first HbA1c level, or the on-line availability of test results on test ordering were evaluated. RESULTS: Evaluation of test intervals showed that 10.3% of all orders and 33.8% of the inpatients' orders were performed within 29 days, 35.5% of all orders and 55% of the inpatients' orders were within 89 days. CONCLUSIONS: Inappropriate laboratory utilization of HbA1c testing is very common especially in the inpatient clinics. We think that the application of the guidelines may decrease unnecessary health expenditure.